378 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Fig. 164 . — Holacanthus arcuatus Gray; after Gunther. 
306. Holacanthus bispinosus Gunther. Plate LVI. 
Total length 8.5 inches; head 3.83 in length; depth 2; eye 4.5 in head; snout 2.5; interorbital 3.6; 
scales about 5-50-18 or 20, the longitudinal scales counted just below lateral line; I>. xm, 19; A. in, 19. 
Body elliptical, compressed, moderately arched from nape to base of first rays of soft dorsal, then 
more abruptly descending to the straight caudal peduncle; ventral Outline more evenly but somewhat 
more deeply arched; caudal peduncle short, about 3 in head, its depth about 2 in head; scales above 
lateral line variable in size and shape, smaller and more rounded than those on the sides below, which 
are mostly much deeper than long; dorsal spines graduated, the last one the longest, about 1.7 in head, 
soft dorsal and anal with rounded angles, the middle rays of dorsal extending to middle of upper 
caudal ray, and of anal to end of first third of lower caudal ray; pectoral shorter than head; ventral 
longer than pectoral about equaling head, its upper rays filamentous, reaching beyond vent nearly 
to first anal spine, the spine about 1.6 in head; fins all densely scaled with small scales. Head short 
and deep, deeper than long, closely scaled; profile steep at its junction with preorbital, concave from 
the protrusion of the muzzle; snout short and bluntly rounded from outward projection of teeth; 
nostrils small, close together in front of eye, the anterior with a small tube prolonged into a small 
triangular flap behind; posterior nostril with a slightly raised ridge in front; opercle unarmed ; sub- 
orbital with few nearly concealed sharp teeth, or none; interopercle without teeth, preopercle along 
its nearly vertical posterior margin with a series of wide-set small sharp teeth, the lowest the longest; 
305. Holacanthus arcuatus Gray. Fig. 164. 
D. xm, 18; A. in, 18; scales 8-48-26; preopercular spine reaching posterior margin of opercle; 
dorsal and anal fins nearly equal in height; a broad, dark-brown band, slightly arched, extending 
from eye to posterior border of dorsal fin; tips of the caudal and a broad border of the anal fin brown; 
the brown marking with a bright border, known from the original type only, which came from the 
Hawaiian Islands; not seen by us. 
Holocanthus arcuatus Gray, Zool. Miscell., 33, 1831 Sandwich Islands; Griffith, Animal Kingdom, Fish., 325, pi. 18, 
Gunther, Cat., ii, 43, 1860 (Gray’s type); Gunther, Fische der Siidsee, II, 50, taf. xxxii, fig. C, 1874 (Sandwich 
Islands; Gray’s type). 
